Since the OP lives in NYC...and I believe I am FAR older than he is, based on the subsequent posts - I get a feeling that I can add to this thread.
My 'old days' were started in 1961 - at a local 'Boys Club'. A class that taught Judo and (Shotokan) Karate...and was mentored by a Judo BB/Shotokan brown belt.

We had no belt levels - only certs of achievement.

That led me a block away to a place called Universal (?) Martial arts -over an ice cream parlor. Church Ave and Flatbush Ave. An older cross road of Brooklyn. There, They taught Kodokan Judo, Shotokan and Kempo . . the main instructor was one Russel Kozuki (Kempo).
The place was ALWAYS ice cold in the winter - they kept the wide roof doors open all the time. The showers were old tile and nothing but cold water...and in the summer? Only the 'welcome office' had a fan blowing. I was almost 10 years old...and one of the very few children there.

The adults were ---some very hard training and hard as nails tough SOB's. Always nice enough to take care of the kids and let us try to hurt them...always tapped us far harder than any street bully did back then.
"Back then'' = a street fight was most usually just punches..at least in a childs level of 'fighting'...and even drunken bar brawls for the adults very rarely included weapons.
A different time.

They were good years for basic and (sometimes) semi solid (mostly Japanese) martial study. Kung Fu came on the scene in the 70's. by then - there were many more forms of Karate available - Goju, Kyokushin, Isshin - and the 'kwans' of TKD.

Most of the schools were less hard core in training dedication than even a basic boxing gym.
Boxers had a limited set of tools and protection (gloves and kidney belts) BUT - they would hit hard...and withing their sportive rules - were quite difficult in the few mixed competitions of the day (Competitions fostered by one Arron Banks and his retinue..a big cash cow for all involved).

Anyway - that was the 60/70's - and many other arts arrived on the scene.
******
And now?

After more than 46 years of involvement in martial arts study - all that I have trained in and experienced in over 30+ of working in forms of law enforcement and personal protection?
I can state that there has NEVER been a better time to find wide and diverse 'old school' training. It is available in many parts of America..if you can get there.
In NYC - it is a simple as a train ride, a relatively moderate fee paid - and the classic blood, sweat, tears and toil.

Personal desires and tastes vary - results vary, but it is available..to those with the passion to find it.

Pick a style - any style...any style at all.
And you can find some of the best around.

My old instructor Mr. Mendoza
*Gave me a bloody nose demonstrating a technique on me, it was my first day of class.
*Did a drill where we had to do flying knees into each other and then a round house to the solar plexus
*Would pull my hair during wrestling because he wanted me to try actual street grappling
*Laughed when I kicked this kid in the leg because he wasn't paying attention
*Swung a large stick at us to jump or duck
I live in a good neighborhood also
you just gotta train in a bad one to find good teachers.